1. Field of the Invention
The present invention relates to a spindle motor and a disk drive apparatus.
2. Description of the Related Art
A hard disk device or an optical disk device is typically equipped with a spindle motor for rotating a disk. The spindle motor includes a stationary unit fixed to a housing of a device and a rotary unit rotating together with a disk supported thereon. In the spindle motor, torque acting about a center axis is generated by magnetic fluxes generated between the stationary unit and the rotary unit, whereby the rotary unit is rotated with respect to the stationary unit.
A conventional spindle motor is disclosed in, e.g., Japanese Patent Application Publication No. 2011-114892. The spindle motor disclosed in the above-cited reference includes a base member, coils and a circuit substrate. Lead wires extending from the coils extend via through-holes of the base member and are connected to the circuit substrate (see claim 1 of Japanese Patent Application Publication No. 2011-114892).
In this spindle motor, there is a need to electrically insulate the lead wires led out from the coils and the base member. Particularly, the spindle motor is becoming thinner and thinner in recent years. Consequently, the diameter of the lead wires making up the coils tends to become smaller. For that reason, if the lead wires having a small diameter make contact with the base member, there is a fear that the lead wires may be damaged by a light contact. Thus, it is desirable to prevent the lead wires and the base member from making contact with each other even under a tensioned state.
However, if an insulation body is merely interposed between the lead wires and the base member, the dimension of the spindle motor is increased by the insulation body. Particularly, the through-holes of the base member are covered with a sealing material such as an adhesive agent or the like. It is not easy to dispose the insulation body between the lead wires and the base member and to reduce the dimension of the spindle motor, while securing the thickness necessary for the rigidity of the base member and the thickness of the sealing material necessary for the sealing of the hard disk device.